package com.njzxw.fs.commonutil.util;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.AbstractRefreshableApplicationContext;
import org.springframework.context.support.AbstractRefreshableConfigApplicationContext;
import org.springframework.stereotype.Component;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.AbstractRefreshableWebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

import javax.servlet.http.HttpServletRequest;

/**
 * @Author 叶开
 * @Date Created in 18:21 2018/5/10 0010
 * @Desc
 */
@Component
public class SpringContextUtils implements ApplicationContextAware {

  /**
   * 上下文对象实例
   */
  private static ApplicationContext applicationContext;

  @Override
  public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
    this.applicationContext = applicationContext;
  }

  /**
   * 获取applicationContext
   *
   * @return
   */
  public static ApplicationContext getApplicationContext() {
    return applicationContext;
  }

  /**
   * 通过class获取Bean.
   *
   * @param clazz
   * @param <T>
   * @return
   */
  public static <T> T getBean(Class<T> clazz) {
    return getApplicationContext().getBean(clazz);
  }

  /**
   * 获取类型为requiredType的对象
   * 如果bean不能被类型转换，相应的异常将会被抛出（BeanNotOfRequiredTypeException）
   *
   * @param name bean注册名
   * @param requiredType 返回对象类型
   * @return Object 返回requiredType类型对象
   * @throws BeansException
   */
  public static Object getBean(String name, Class requiredType)
          throws BeansException {
    return applicationContext.getBean(name, requiredType);
  }

  /**
   * 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true
   *
   * @param name
   * @return boolean
   */
  public static boolean containsBean(String name) {
    return applicationContext.containsBean(name);
  }

  /**
   * 判断以给定名字注册的bean定义是一个singleton还是一个prototype。
   * 如果与给定名字相应的bean定义没有被找到，将会抛出一个异常（NoSuchBeanDefinitionException）
   *
   * @param name
   * @return boolean
   * @throws NoSuchBeanDefinitionException
   */
  public static boolean isSingleton(String name)
          throws NoSuchBeanDefinitionException {
    return applicationContext.isSingleton(name);
  }

  /**
   * @param name
   * @return Class 注册对象的类型
   * @throws NoSuchBeanDefinitionException
   */
  public static Class getType(String name)
          throws NoSuchBeanDefinitionException {
    return applicationContext.getType(name);
  }

  /**
   * 如果给定的bean名字在bean定义中有别名，则返回这些别名
   *
   * @param name
   * @return
   * @throws NoSuchBeanDefinitionException
   */
  public static String[] getAliases(String name)
          throws NoSuchBeanDefinitionException {
    return applicationContext.getAliases(name);
  }

  public static void reload() {
    AbstractRefreshableApplicationContext abstractRefreshableApplicationContext = (AbstractRefreshableApplicationContext) applicationContext;
    abstractRefreshableApplicationContext.refresh();
  }

  public static void reload(HttpServletRequest request) {
    WebApplicationContext context = WebApplicationContextUtils.getWebApplicationContext(request.getSession().getServletContext());

    if (context.getParent() !=null){
      ((ConfigurableApplicationContext) context.getParent()) .refresh();
    }else{
      ((AbstractRefreshableApplicationContext)context).refresh();
    }
  }

}
